If the Supreme Court strikes down same-sex marriage bans, it may well do so on the grounds that they violate the dignity of gay couples. And although proponents of marriage equality may cheer a decision along these lines when it is delivered, the expansion of the constitutional right to dignity may produce far-reaching consequences that they will later have cause to regret.

The oral arguments at the Supreme Court on Tuesday made clear that Justice Anthony Kennedy’s biggest contribution to the gay-marriage debate is his expansion of constitutional protections for the right to dignity. Justice Kennedy invoked the word “dignity” five times in the oral arguments; and other lawyers invoked it 16 times. It was central to the opening statements of Solicitor General Don Verrilli. “The opportunity to marry is integral to human dignity,” he began. “Excluding gay and lesbian couples from marriage demeans the dignity of these couples.” It was also one of the first words uttered by the plaintiff’s lawyer, Mary L. Bonuato. “If a legal commitment, responsibility and protection that is marriage is off limits to gay people as a class,” she said, “the stain of unworthiness that follows on individuals and families contravenes the basic constitutional commitment to equal dignity.”

Although the word dignity has appeared in more than 900 Supreme Court opinions, Justice Kennedy, as Kenji Yoshino of NYU has noted, has been especially drawn to it. He has referred to “dignity” in cases ranging from partial-birth abortions to prisons. As Yoshino puts it, “When Justice Kennedy ascribes dignity to an entity, that entity generally prevails.” Kennedy’s recognition of the dignity interests of LGBT couples has been influential in persuading lower court judges to strike down bans on same-sex marriage. But although Kennedy’s description of the dignitary interests of LGBT couples is inspiring, and it accurately describes their social experience, the roots of the right to dignity in constitutional text, history, and tradition are harder to discern.

Kennedy first drew a clear connection between “personal dignity and autonomy” and laws regulating personal relationships such as marriage in the 1992 Casey decision, which upheld the core of Roe v. Wade:

Our law affords constitutional protection to personal decisions relating to marriage, procreation, contraception, family relationships, child rearing, and education … These matters, involving the most intimate and personal choices a person may make in a lifetime, choices central to personal dignity and autonomy, are central to the liberty protected by the Fourteenth Amendment. At the heart of liberty is the right to define one's own concept of existence, of meaning, of the universe, and of the mystery of human life. Beliefs about these matters could not define the attributes of personhood were they formed under compulsion of the State.

When Justice Kennedy later invoked this idea of dignity to overturn laws banning same-sex intimacy in the 2003 Lawrence case, Justice Scalia ridiculed his opinion in Casey as the “famed sweet-mystery-of-life passage.” Despite Scalia’s mocking tone, he was correct to note that Kennedy’s constitutionalizing of a right to dignity expanded the already amorphous right to privacy recognized in Roe v. Wade, which itself had tenuous constitutional roots. By rooting the right to dignity in a synthesis of the textually enumerated rights of equality and liberty, Kennedy laid the groundwork for judges to review laws that inflicted dignitary harm with skepticism, regardless of proof of intentional animus and regardless of whether the victim of discrimination was considered a “suspect class.”

A range of liberal scholars recognized the sweeping implications of Kennedy’s new synthesis of dignity with liberty and equality, from Robert Post (who observed that in Lawrence, the Court relied on “themes of respect and stigma ... traditionally associated with equal protection”) to Laurence H. Tribe (who described a “Substantive due process-equal protection synthesis,” and the relationship between the two as a “double helix”) to William N. Eskridge (who called the connection between liberty and equality a “jurisprudence of tolerance”). But in discussing the dignitary interest that emerges from the equality and liberty clauses, all of these scholars relied on the same highly abstract penumbral reasoning that had proven so controversial in the cases leading up to Roe v. Wade. In other words, the kind of liberties that the Framers had in mind when they framed the Fourth Amendment (the liberty of the home) were very different, and far more specific, than the broad right to be free to define your own identity without being demeaned by the state or by fellow citizens that Kennedy recognized in Lawrence.

Kennedy made another crucial move in Lawrence, concluding that an individual’s interest in dignity trumps the majority’s interest in preserving traditional moral values. “The fact that the governing majority in a State has traditionally viewed a particular practice as immoral is not a sufficient reason for upholding a law prohibiting the practice,” Kennedy held.

“This effectively decrees the end of all morals legislation,” Justice Scalia fulminated, and he predicted the demise of “state laws against bigamy, same-sex marriage, adult incest, prostitution, masturbation, adultery, fornication, bestiality, and obscenity.” In fact, Scalia’s prediction may prove to be correct. His question about why the state’s police power to protect public morals—taken for granted from the founding era until the Lawrence case—was suddenly a violation of the Constitution remains valid and unanswered. In Lawrence, Scalia also predicted that the new dignitary right would lead inevitably to the recognition of same-sex marriage, despite Kennedy’s protestations to the contrary (“Do not believe it,” Scalia wrote). As Scalia understood, without moral disapproval as a permissible state interest, the other interests the state offered to ban same-sex unions were hard to credit. Here is Scalia’s prescient observation:

If moral disapprobation of homosexual conduct is “no legitimate state interest” for purposes of proscribing that conduct; and if, as the Court coos (casting aside all pretense of neutrality), “[w]hen sexuality finds overt expression in intimate conduct with another person, the conduct can be but one element in a personal bond that is more enduring,” what justification could there possibly be for denying the benefits of marriage to homosexual couples exercising “[t]he liberty protected by the Constitution?”

“Surely not the encouragement of procreation,” Scalia concluded, “since the sterile and the elderly are allowed to marry.”

In other words, despite Ohio’s attempt to resurrect the encouragement of procreation as a justification for same-sex marriage bans in the recent arguments—a justification dismantled by Justices Kagan and Sotomayor—Scalia beat them to the punch by more than a decade.

In addition to sincere moral disapproval of homosexuality by some religious people, there is one other main reason that voters have passed same-sex marriage bans in the past few years: a desire to preserve tradition. But the Supreme Court ruled that reason out of bounds in United States v. Virginia in 1996, when it held that a desire to preserve tradition for its own sake was a “notably circular argument” that could not survive constitutional scrutiny.

Since these two arguments—moral disapproval or preserving tradition—are the real reasons most voters have for supporting gay marriage bans, opponents of gay marriage were forced to offer implausible reasons—such as promoting “responsible procreation” by straight people—which, as Justice Kagan’s questioning suggested, are hard to credit because they are essentially made up for the purposes of litigation.

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Justice Kennedy’s broad constitutionalizing of a right to dignity has boxed in gay marriage opponents with its scope and breadth. Chief Justice Roberts tried to narrow the implications of the Lawrence decision in the oral arguments yesterday by suggesting that in that case, “the whole argument is the State cannot intrude on that personal relationship. This, it seems to me, is different in that what the argument is [today] is the State must sanction. It must approve the relationship. They’re two different questions.” But Solicitor General Verrilli resisted the attempt to narrow the dignitary implications of Lawrence. “Lawrence catalyzed for our society,” he replied. “It put gay and lesbian couples, gay and lesbian people, in a position for the first time in our history to be able to lay claim to the abiding promise of the Fourteenth Amendment in a way that was just impossible when they were marginalized and ostracized.”

Verrilli’s insight that denial of marriage benefits to gays and lesbians could demean and ostracize them, and violate their dignity, was confirmed by Justice Kennedy’s opinion the Windsor case from 2013, striking down the federal Defense of Marriage Act. According to Kennedy, DOMA’s history of enactment and its own text demonstrate that interference with the equal dignity of same-sex marriages was “the essence” of its effects on gay people.

I won’t rehearse here the objections to reading the text and history of the Constitution at such a high level of generality; with this approach, the connections to the specific concerns that animated the framers is hard to discern. Suffice it to say that Justice Louis Brandeis, the greatest defender of the right to privacy in U.S. history, originally tried to persuade courts to recognize a new right to dignity, after confessing that American law, unlike Roman and European law, had not, traditionally protected offenses against honor and dignity.

But, as Neal Richards demonstrates in Intellectual Privacy, Brandeis changed his mind about the wisdom of constitutionalizing a right to dignity—defined as the right to restrain the press from publishing truthful but embarrassing information about celebrities—after concluding that it clashed with the First Amendment guarantees of free press and free expression. Instead, Brandeis came to embrace a more carefully defined notion of intellectual privacy and freedom of thought and belief, more closely rooted in the text of the First Amendment itself.

There is no doubt that Justice Kennedy accurately and movingly describes the indignity and stigma that bans on same sex marriage impose on the right of LGBT citizens to define their own identities and to claim the benefits of equal citizenship. But constitutionalizing that injury with broad abstractions like dignity may lead to results in the future that liberals come to regret. Already, the European Court of Justice’s recognition of a sweeping “Right to be Forgotten” on the Internet has lead to the most dramatic clash between European traditions of protecting dignity and American traditions of protecting free speech in a generation.

And down the line, the right to dignity—now celebrated by liberals for what it means to gay rights—could ultimately produce other decisions in unrelated cases that they would not be so quick to celebrate. In the McDonald case, striking down gun possession laws under the Second Amendment, Justice Scalia recognized a dignitary interest attached to the right to bear arms. “[T]he conceptual core of the liberty clause ... pertains to ... [an individual’s] [s]elf-determination, ... dignity [or] respect,” he wrote.

The word dignity eludes narrow definition, or for that matter, any generally agreed upon definition. The Court itself has not provided a clear definition of dignity. One scholar, William A. Parent, declares, “[D]ignity is to possess the right not to be arbitrarily and therefore unjustly disparaged as a person.” In another article on “the Jurisprudence of Dignity,” Leslie Meltzer Henry writes that there is no single definition, but that dignity includes various conceptions including institutional status, equality, liberty, individual integrity, and collective virtue. She concludes, “dignity’s conceptions and functions are dynamic and context-driven.”

If dignity is defined so elastically, then conservatives judges might invoke it to strike down not only gun-control laws, but also other progressive legislation. Libertarian groups invoked the “sweet-mystery-of-life” my language in Casey to argue that the Obamacare healthcare mandate unconstitutionally violated the dignity and autonomy of Americans by forcing them to buy health insurance. In the future, cigarette smokers might argue that anti-smoking bans violate their ability to create an individual identity. And conservative Christian wedding photographers could claim that anti-discrimination laws compelling them to photograph gay weddings violate their dignity and ability to define themselves as conservative Christians. What courts would do when confronted with the clashing dignitary rights of the religious wedding photographer and the gay couple, or the hunter and the victim of gun violence, is anyone’s guess, because dignity is such an abstract concept that its boundaries are difficult to discern.

In suggesting that the expansion of the right to dignity is something that liberals may come to regret, I’m not arguing that same-sex marriage bans can or should easily be upheld in light of the Supreme Court precedents on the books. In the same-sex marriage arguments, the liberal justices seemed drawn to the idea that marriage is a fundamental right that must be expanded to all citizens on equal terms. A decision along those lines—although broader in some respects than a ruling based on dignity—might be easier to confine to cases involving marriage. And given Justice Kennedy’s previous opinions for the Court ruling out of bounds moral disapproval and the preservation of tradition for its own sake, it’s hard to think of any other plausible reasons for upholding the marriage bans that don’t rely on what the Court has defined as animus. Still, if the Court strikes down same-sex marriage bans on the grounds that they violate a right to dignity, liberals may have second thoughts about empowering judges to decide whose dignity trumps when the interests of citizens with very different conceptions of dignity clash.